In order to permit a truck driver to control painting of stripes along a highway from the truck cab while driving and following a painting pattern formulated by a previously painted stripe, a set of pre-aligned markers, or the edge of the road, there have been developed video monitoring systems for both monitoring the marked path and for monitoring the painted stripes which are laid down at the rear end of the truck. For example, C. F. Brown, Jr. in U.S. Pat. No. 3,101,175, Aug. 20, 1963 for ROAD STRIPING MACHINE WITH ELECTRONIC SIGHT has a video monitor in the truck cab for monitoring the truck position relative to the pattern being followed. Another example, as depicted in FIG. 4, is a commercial highway striping system available from Graco, Inc., Minneapolis, Minn. with a truck cab mount video monitor and painting control system communicating with a towed trailer paint striping system having a video camera viewing the stripes being painted at the rear of the trailer. Thus, the single driver-operator can visually follow an existing roadway stripe for example and monitor the results on the video monitor without having to look backward and take attention off the roadway.
However, in such towed trailer or rear mount truck paint striping systems, there is a significant tracking problem in painting stripes having a curved pattern, since the rear end does not track around a curve similarly to the front end of the truck where the driver sights and follows a striping pattern such as a previous stripe, a set of markers previously laid down, or the edge of the road.
As evidenced by W. R. Mitchell in U.S. Pat. No. 3,286,928, Nov. 22, 1966 for HYDRAULIC COMPENSATION OF HIGHWAY STRIPING EQUIPMENT, it is known that the problem of compensating for mistracking encountered in following highway stripe markers about curves in the highway when rear painting gun mounts are mounted behind a truck can be solved by employment of a hydraulically driven servo system linked to the truck steering system to laterally move the paint striper gun to compensate for the tendency to mistrack. However, this requires an expensive, complex servo system that introduces its own set of problems in operation and the custom installation of the servo system on a dedicated highway striping truck.
Other systems of compensation require steering by a second striper person riding a steerable trailer being towed behind the truck, such as the trailer disclosed in J. P. Oakley's U.S. Pat. No. 3,540,358 of Aug. 21, 1968 for MARKER BUTTON SETTER. The requirement of a two man painting crew, one to drive and one to steer is too labor intensive to use for many competitive striping operations.
Furthermore, there is in the prior art an assortment of several different types of mutually incompatible special purpose striping systems, such as walk-behind slow speed stripers, highway truck high speed stripers, and intermediate speed tractor pushed riding stripers. This requires a large inventory of dedicated equipment for handling various small scale and large scale striping jobs.
Other complicated types of stripers require multiple person crews for operation, one to drive-one to paint, for example, or one to drive and two to lift heavy paint barrels into place on a truck bed. However, there is no known universal system that can be idealistically operated by one person to implement with the same paint striping system (a) slow speed manually hand driven parking lot striping, (b) a ride-on intermediate speed striper for airport runway striping, and (c) a high speed single or multiple stripe truck propelled striping system.
There is also the auxiliary problem in the line striping industry of a dedicated special purpose truck with built-in paint striping features that cannot usually be used for other purposes.
Thus, this invention has the objective of providing a striping system that is universal enough to excell at slow, intermediate and high speed striping operations under control of a single driver-operator.
More specifically this invention has the objective of providing a system which does not require an extra operator to steer, to load paint, or to share the painting chores with the driver.
Additionally this invention has the objective to provide an integrated modular paint striping system that excells at low, intermediate or high speed striping and which does not require a dedicated tow truck, but operates from a multi-use truck such as a pick-up truck and requires only a single driver-operator.
A further object of this invention is to release the paint striper tow truck for other purposes when not employed for striping.
Another object of the invention is to provide a modular paint striping system that comprehensively covers various paint striping jobs, small and large, with a single operator that drives, stripes and converts the modular system to sub-systems for off-highway use.
Other objects, features and advantages of the invention will be found throughout the following description, drawings and claims.